Life-cycle analysis or assesment (LCA) is a scientific method to record environmental (but also increasingly including social) impacts "from cradle to grave", i.e. from production to final disposal / recycling. Also known as "well to wheel" for transport fuels or "field to wheel" for biofuels.

Two of the most used types of life cycle assessment for bioenergy are those used to determine net-energy and net greenhouse gas emissions. In order to investigate the environmental impacts of bioenergy and biofuels it is absolutely necessary to account for several other problems as acidicication, nutrification, land occupation, water use or toxicological effects of fertilizers and pesiticides.

Contents

Summary

LCA aims to calculate the environmental impact of a good, a process or a service "from cradle to grave". The impact includes all relevant environmental aspects such as cumulative energy demand, climatic change, acidification, nutrification, land occupation, photochemical oxidation, ecotoxicity, human health, etc.. After quantifying the energy and substances flows occuring at each step of the product/service life cycle (Life Cycle Inventory or LCI), the Life Cycle Impact Assessment (LCIA) transpose these flows into a potential impact, as per the main damage categories (as listed above). The results are mainly used in comparative approaches, in order to compare several scenarios ending with the same functional unit. For instance, the functional unit "transporting one person on one kilometer" can be used to compare several types of transport.

News

"A recently published article in the peer-reviewed Journal of the Royal Society Interface suggests that in order for life cycle analyses (LCA) of biomass-based products such as biofuels to be most accurately calculated, modelers should develop a hybridized methodology that considers both direct and indirect effects, to measure the carbon intensity of production. Further, the authors of the paper stressed the need for policymakers worldwide to develop methodologies that are compatible and comparable, rather than continue forward with the patchwork of individualized policies specific to country or region."

"Susan Tarka Sanchez served as lead author of the paper, titled 'Accounting for Indirect Land Use Change in the Life Cycle Assessment of Biofuel Supply Chains,' while working as the senior scientist at California-based business and environmental consulting firm Life Cycle Associates LLC, the company which developed the CA-GREET life cycle analyses model used by the California Air Resources Board in developing the state’s low carbon fuel standard. Sanchez admits that indirect land use change (ILUC) continues to be a controversial topic, but said the group of international experts that contributed to the journal paper feel it is essential to incorporate indirect effects into biofuels methodology in order to gauge the full effects of the product." [1]

Environmental burden shifting and sustainability criteria for biofuels, 26 March 2012 by Anil Baral for ICCT blog: "Biofuels are here for three reasons – climate change mitigation, energy security and to increase rural incomes. The supposed climate change mitigation potential of biofuels comes with the idea that renewability implies carbon neutrality. However, with the introduction of the systems approach of analyzing environmental costs and benefits, it has emerged that biofuels, especially first generation biofuels, do not offer environmental and human health benefits on all fronts. The systems approach, such as life cycle analysis (LCA), looks into far ranging impacts including GHG emissions from indirect land use change (ILUC). We find that in many cases we may not expect to achieve net greenhouse gas reductions from biofuel policies – but also that even where climate change mitigation might be effective, there can be other tradeoffs in choosing biofuels, indicating a potential risk of environmental burden shifting for policies that solely focus on GHG mitigation." [2]

"U.S. District Judge Lawrence O'Neill issued a preliminary injunction that ruled the California Air Resources Board's low-carbon fuel regulations violated the U.S. Constitution's commerce clause by discriminating against crude oil and biofuels producers located outside California."

"The regulations require producers, refiners and importers of gasoline and diesel to reduce the carbon footprint of their fuel by 10% over the next decade, as part of California's landmark global-warming law aimed at reducing greenhouse gas emissions to 1990 levels by 2020."

"The regulation calculates the life cycle of fuels from their extraction — or cultivation, in the case of biofuels such as corn-based ethanol — to their combustion. For example, the state considers how corn is grown, harvested and converted to ethanol intended for California gas tanks, a life-cycle evaluation called 'seeds to wheels.'..."[3]

"The research team used agricultural survey data from Brazil to calculate emissions of air pollutants and greenhouse gases from the entire production, distribution, and lifecycle of sugarcane ethanol from 2000 to 2008."

"The estimated pollutants were 1.5 to 7.3 times higher than those from satellite-based methods, according to lead author Elliott Campbell of the University of California, Merced."[4]

Rethinking Life-Cycle Fuel Regulations, 20 August 2011 by Forbes: "In the most recent issue of Climatic Change, one of the resident geniuses that populate the faculty of the University of Michigan School of Natural Resources and Environment, Dr. John DeCicco, argues that attempting to regulate fuels using a lifecycle analysis (LCA)-based approach—as is currently done by California’s Low Carbon Fuel Standard and the U.S. Renewable Fuel Standard—is an exercise in futility for purposes of gaging environmental effectiveness."

"Instead, in 'Biofuels and carbon management,' DeCicco proposes a method using annual basis carbon (ABC) accounting to track the stocks and flows of carbon and other relevant greenhouse gases (GHGs) throughout fuel supply chains."

"ABC accounting would avoid an automatic credit of biogenic carbon in biofuels, and minimize and accumulation of carbon debt due to indirect land-use change, he says."

"Upon reflection, policy is best defined using current-period accounting of carbon stocks and flows, ideally with direct, measurement-based, verifiable tallies of GHG emissions from the production and use of all fuels and feedstocks."[5]

"For the nearly four-year study, researchers conducted a life cycle analysis on 14 diesel and jet fuel sources made from feedstocks, and identified the key factors that make a difference in whether a biofuel is truly an environmental improvement over conventional jet fuel."

"Biofuels made from jatropha oil, for example, can have a low carbon footprint because the byproduct husks, shells, and meal from jatropha plants can be used for fertilizer, animal feed, and electricity generation."

"But the study found that many biofuel carbon footprints are based on where and how it's grown."

"The study suggested that easy-to-grow algae or salicornia, neither of which requires nutrient-rich soil, might be more effective biomass options for biofuels than crops requiring acres and acres of farmland."[6]

"EPA in January backed off applying greenhouse gas permitting rules to power plants and other facilities that use plant matter to make energy."

"EPA said it would use the three-year delay to improve methods for accounting for the carbon footprint of using various types of forest and other plant materials. On Wednesday, the agency is slated to publish a request for nominations to serve on a panel of EPA’s Science Advisory Board that will weigh the matter."

"A key question is how to track carbon released from land-use changes related to harvesting plant matter."

"EPA has come under heavy pressure from the forest industry and some Capitol Hill lawmakers fearful that applying emissions rules to biomass would stymie the market for the energy source."[7]

Campaigners should support aviation industry biofuel trials, 20 April 2011 by Paul Steele of the Air Transport Action Group in The Ecologist: "Having seen the issues caused by road transport’s use of first generation sources, the aviation industry has been proactive in trying to ‘do it right,’ from the start. At the same time, the aviation industry does not have the luxury of a variety of renewable energy sources like other sectors (wind, solar, hydrogen etc) and is therefore focussed on developing second generation sustainable biofuels as a means of reducing GHG emissions."

"In fact, a recent Yale University study showed that jatropha plantations in Brazil are able to have as much as an 85 per cent decrease in lifecycle carbon emissions, when grown in a responsible way. But jatropha is just one potential source of biofuel for aviation – a range of non-food crops and advanced biomass sources such as algae promise to provide low-carbon fuel for air transport."[8]

"Jatropha has been planted across Asia in countries under pressure from the West to reduce emissions from the destruction of rainforests, car exhausts and energy production from coal-burning power plants."

"But the study for the anti-poverty agency ActionAid and the RSPB of a proposed 50,000 hectare jatropha plantation development in the Dakatcha woodlands of Kenya, near Malindi, found that emissions in producing the biofuel would be 2.5 to six times higher than the fossil fuel equivalents. The woodland hosts globally endangeredbird life."

"The research examined the whole 'life-cycle' of the jatropha production, primarily the clearance of woodland and scrubland, planting, harvesting, refining and transportation of the bio-diesel destined for heating and electricity production in Europe."[9]

"CO2 emissions resulting from bioenergy production have traditionally been excluded from most emission inventories and environmental impact studies because bioenergy is carbon- and climate- neutral as long as CO2 emissions from biofuel combustion are sequestered by growing biomass."

"The authors propose that CO2 emissions from biomass combustion for bioenergy should no longer be excluded from Life Cycle Assessment studies or be assumed to have the same global warming potential as anthropogenic CO2 emissions. Carbon dioxide is emitted when biomass is burnt and the sequestration in the new vegetation can be spread for up to several decades in the case of slow-growing biomass, like forests."

"The authors believe that the global warming potential of CO2 emissions from bioenergy production depends on the interactions with the full carbon cycle and its sinks, the oceans and the terrestrial biosphere, which work on different time scales."[10]

Midwest senators strike back with pro-biofuels bill, 11 March 2011 by Ethanol Producer Magazine: "Two Midwest senators proposed legislation March 10 favoring the build-out of biofuels infrastructure and continued federal support of ethanol and biodiesel. The Securing America’s Future with Energy and Sustainable Technologies Act, introduced by Sens. Amy Klobuchar, D-Minn., and Tim Johnson, D-S.D., would establish incentives for biofuels infrastructure and deployment, develop a 'more cost-effective' tax credit program for ethanol and biodiesel, establish a renewable energy standard and encourage greater production of hybrid, electric and flex-fuel vehicles (FFVs)."

"The 117-page SAFEST Act covers a wide spectrum of renewable fuels interests and contains several important provisions related to the ethanol industry....The legislation also includes text that would prevent the U.S. EPA from considering international indirect land use changes when calculating biofuels’ lifecyclegreenhouse gas (GHG) emissions and calls for the National Academies of Science to conduct a review of methodologies used to project indirect GHG emissions relating to transportation fuels."[11]

In face of hunger, corn ethanol industry says blame anyone but us, 14 February 2011 by Switchboard.nrdc.com: "In a Washington Post editorial last week, biofuels expert Tim Searchinger sheds much needed light on the link between two important trends in today’s markets for grains: the expansion of global biofuels mandates on the one hand and the frequency and magnitude of food shortages around the world on the other."

"Where Searchinger lays out how in a complicated and complex market, biofuels make a bad situation worse, the industry cries for the messenger’s head and tries to shift the blame to anyone but themselves."

"This now prominently features attacks on the science of lifecycle greenhouse gas emissions accounting for biofuels, including the need to account for the carbon that is emitted when forests and other uncultivated lands are cleared for food production as a result of existing cropland being diverted towards growing grains for fuel."[12]

"'California has always been an important market for biofuels like ethanol,' Cooper said. 'The LCFS will have significant implications for the future role of ethanol in the state.'"

"Specifically, the topics addressed by the advisory panel will include the program’s progress against LCFS targets, possible adjustments to the compliance schedule, lifecycle assessments, advances in fuels and production technology, fuel and vehicle supply availability, the program’s impact on the state’s fuel supplies, and other issues."[13]

"Many of the early efforts at green labeling utilized life cycle inventory data that were inapplicable to actual countries of product origin..."

"Here's a key cite from the Advertising Age article on this:"

"Christopher Cole, an advertising-law specialist and partner with law firm Manatt Phelps & Phillips in Washington, said the guides could render most of the more than 300 environmental seals of approval now in currency on packaging and products largely useless and possibly in violation of FTC standards."[15]

"The three U.S. researchers say their results suggest that 'the most water-efficient, fossil-based technologies have an EROWI one to two orders of magnitude greater...than the most water-efficient biomass technologies, implying that the development of biomass energy technologies in scale sufficient to be a significant source of energy may produce or exacerbate water shortages around the globe and be limited by the availability of fresh water."[16]

The decision adopted by consensus was that "[T]he blend obtained by a retailer/blender by mixing RSB compliant biofuels from various sources, shall have 50% lower GHG emissions than fossil fuel on average. Such blend of biofuels or a neat biofuel (i.e. pure biofuel sold unblended) cannot make any claim of compliance if it does not reduce GHG emissions by 50%."

In addition, 'all individual RSB compliant biofuels shall have lower GHG emissions over their life cycle, compared to the fossil fuel baseline".[17]

Klobuchar bill: trojan horse for bad biofuels, 14 July 2010, Nathanael Greene’s Blog/NRDC: "It should come as no surprise that the first copy of the full text of Sen Klobuchar's energy bill was found on a corn ethanol industry association website; the bill reads like the industry's wish list."

Big Meat: Fueling Change or Greenwashing Fuel?, 3 June 2010 by Anna Lappé in The Atlantic: "On January 13, 2009, Tyson—one of the world's largest processors of chicken, beef, and pork—and the fuel company Syntroleum broke ground in Geismar, Louisiana, on a 'renewable' diesel plant. The fuel will be produced in part with Tyson factory farm byproducts, including animal fat and poultry litter."

"Tyson claims these facilities produce eco-friendly, cleaner-burning fuels from scraps that would otherwise be wasted. But critics beg to differ....They charge that this fuel is renewable only in the narrowest sense, if you ignore the complete life cycle of its production. The fuels depend on energy-intensive, greenhouse-gas-emitting confined animal feeding operations (CAFOs), which require feed raised with methods that deplete topsoil and overuse synthetic fertilizer, contributing to carbon dioxide emissions."[19]

"The legal challenge results from the EPA using optimistic projections about emissions from biofuel production in 2022, rather than current data regarding emissions from biofuel production, to finalize lifecycle greenhouse emissions assessments. Using this flawed method, the EPA determined that all biofuels meet 2007 emissions standards, despite a growing body of research that indicate some biofuels result in worse emissions than conventional gasoline."[20]

"When the Environmental Protection Agency revised its renewable fuel standards in February, the agency recalculated the lifecycle emissions of corn ethanol to find that it was 20 percent less greenhouse-gas emitting than gasoline and, therefore, qualified as a renewable fuel. Some wondered what had changed since an EPA review issued less than a year before found that emissions from corn ethanol were too high for it to qualify."

"As it turns out, none of the actual data about emissions from biofuels changed — just the way the EPA presented it....Specifically, the agency's new fuel standards assess each biofuel based on its assumed greenhouse gas emissions in the year 2022, the deadline by which renewable fuel production must be at levels mandated by the Energy Security and Independence Act of 2007."

But focusing on the amount biofuels are expected to emit in 2022 'distorts the picture of today's biofuels,' according to Jeremy Martin, a senior analyst in the Union of Concerned Scientists' Clean Vehicles Program."

"Even the EPA's own analysis 'shows that, in the near term, natural-gas-powered, dry-milled corn ethanol production results in an increase of greenhouse gas emissions of 12 to 33 percent compared to gasoline,' says Joe Fargione, a lead scientist at the Nature Conservancy."[21]

"Adopted by the California Air Resources Board in 2009, the LCFS is intended to reduce California greenhouse gas (GHG) emissions by reducing the carbon intensity of transportation fuels used in California by an average of 10 percent by the year 2020. Carbon intensity is a measure of the direct and indirect GHG emissions associated with each step of a fuel’s full life-cycle – the 'well-to-wheels' for fossil fuels and 'seed-to-wheels' for biofuels."

"For corn ethanol, indirect land use changes are a significant source of additional GHG emissions....Given the LCFS’ requirement of reduced carbon intensity, it’s not difficult to see that corn ethanol will be severely disadvantaged in California."[23]

"'From a representative sample of [lifecycle] studies on biofuels, less than one third presented results for acidification and eutrophication, and only a few for toxicity potential (either human toxicity or eco-toxicity, or both), summer smog, ozone depletion or abiotic resource depletion potential, and none on biodiversity,' it adds."

"The study is the second major report this month calling for greater research on the environmental effects of producing ethanol and other renewable transportation fuels.

"A Government Accountability Office report released Oct. 2 said Congress should require U.S. EPA to consider a wider range of environmental effects when deciding which fuels are eligible under the federal biofuels use mandate."[24]

"House Agriculture Committee Chairman Collin Peterson (D., Minn.) said the review panel expressed concern about using incomplete and unreliable models to indirect land use changes and indicated they didn't have enough time to review this 'convoluted and complicated proposal.'"

"Ethanol groups said the agency 'stacked the deck against biofuels' in its peer review process. The Renewable Fuels Association (RFA) criticized EPA for selecting 'peers' who have been vocal opponents of biofuels or who have released studies later called into question".[25]

"The high level of uncertainty created by model incompatibility and by aggregate agricultural models not capable of capturing necessary refinements in LUC and agricultural management practices has led to two positions on including indirect LUC in LCA models. First, we know that indirect LUC and associated GHG emissions are not zero, so we are doing a disservice to society by not including them in LCA estimates, even though the “confidence interval” is extremely wide (Hertel et al., 2010). Second, we do not have the tools to obtain a reasonably accurate estimate of the GHG emission effects of indirect LUC, and we are doing a disservice by trying to measure the unmeasurable (Babcock, 2009b)."

"Although there are a number of qualifiers, the same LCA model should be used to derive GHG

emission estimates when comparing different feedstocks or different fuels since cross-model comparisons
simply highlight model differences (i.e., it is important to create a stable market environment when
comparing fuels). Yet, in order to provide a complete understanding of the sensitivity of LCA results and
policy impacts to model assumptions, it is important to consider alternative LCA models (and
assumptions)." [[27]

Accounting for Indirect Land Use Change in the Life Cycle Assessment of Biofuel Supply Chains by Susan Tarka Sanchez, Jeremy Woods, Mark Akhurst, Matthew Brander, Michael O'Hare, Terence P. Dawson, Robert Edwards, Adam J. Liska and Rick Malpas, March 2012. "We analyse the use of life cycle analysis (LCA) for estimating the carbon intensity of biofuel production from indirect land-use change (ILUC). Two approaches are critiqued: direct, attributional life cycle analysis and consequential life cycle analysis (CLCA)...We conclude that CLCA is applicable for estimating the historic emissions from ILUC, although improvements to the hybrid approach proposed, coupled with regular updating, are required, and uncertainly values must be adequately represented; however, the scope and the depth of the expansion of the system boundaries required for CLCA remain controversial." [28]

From abstract: "Life cycle assessment of greenhouse gas emissions associated with biofuels should not only consider fossil fuel inputs, but also N2O emissions and changes in carbon stocks of (agro) ecosystems linked to the cultivation of biofuel crops. When this is done, current plant oils such as European rapeseed oil and oil from soybeans and oil palms cultivated on recently deforested soils have higher life cycle greenhouse gas emissions than conventional diesel."

From the abstract: "In this review we explore some of the more complicated sources of differences in findings related to LCA methodology by reviewing 67 LCA studies published between 2005 and 2010. A very important and particularly difficult problem to solve is coproduct allocation....The treatment of biogenic carbon is another important issue."[30]